Hydrogen is a green clean fuel and chemical feedstock. Its separation and purification from hydrogencontaining mixtures is the key step in the production of hydrogen with high purity(>99.99%). In this work, carbon ...Hydrogen is a green clean fuel and chemical feedstock. Its separation and purification from hydrogencontaining mixtures is the key step in the production of hydrogen with high purity(>99.99%). In this work, carbon molecular sieve(CMS) membranes with ultrahigh permselectivity for hydrogen purification were fabricated by high-temperature(700–900 ℃) pyrolysis of polymeric precursor of phenolphthaleinbased cardo poly(arylene ether ketone)(PEK-C). The evolution of the microstructural texture and ultramicroporous structure and gas separation performance of the CMS membrane were characterized via TG-MS, FT-IR, XRD, TEM, CO2 sorption analysis and gas permeation measurements. CMS membranes prepared at 700 ℃ exhibited amorphous turbostratic carbon structures and high H2 permeability of 5260 Barrer with H2/CH4, H2/N2 and H2/CO selectivities of 311, 142, 75, respectively. When carbonized at900 ℃, the CMS membrane with ultrahigh H2/CH4 selectivity of 1859 was derived owing to the formation of the dense and ordered carbon structure. CMS membranes with ultrahigh permselectivity exhibit an attractive application prospect in hydrogen purification.展开更多
Tissue-engineered cartilage regeneration by bone marrow stromal cells(BMSCs)is considered an ideal method.However,how to regulate BMSCs to regenerate specific types of cartilage remains unclear,which significantly lim...Tissue-engineered cartilage regeneration by bone marrow stromal cells(BMSCs)is considered an ideal method.However,how to regulate BMSCs to regenerate specific types of cartilage remains unclear,which significantly limits its clinical translation and leads to suboptimal clinical effects.Herein,we systematically explored the role of native ear and articular cartilage niches on the differentiation fate of BMSCs and the type of regenerated cartilage.First,we prepared two types of acellular cartilage sheets(ACSs)and two types of chondrocytes.Then green fluorescent protein-labeled BMSCs were seeded on two types of ACSs with or without corresponding types of chondrocytes using a sandwich model and directed or cross-implanted them into native cartilage niches.After one year of in vivo culture,cell tracking and the results of histological results showed that the native cartilage niches were capable of regulating BMSCs regeneration into specific types of cartilage that were consistent with the cartilage types of the implanted sites.Furthermore,even when the type of niche formed by ACSs or the biomimetic cartilage niche constructed by specific types of ACSs and specific types of chondrocytes did not match with the native cartilage niche,the native cartilage niche continued to determine the type of cartilage regenerated by implanted BMSCs and chondrocytes.All our results provide sufficient evidence for specific types of cartilage regeneration using chondrogenic potential cells,such as mesenchymal stem cells and chondrocytes.展开更多
基金the National Key R&D Program of China(2017YFB0603403)National Natural Science Foundation of China(21676044,21878033,21978034)+1 种基金High Level Innovation Team of Liaoning Province(XLYC1908033)Fundamental Research Funds for the Central Universities(DUT19ZD211,DUT 2018TB02)for the financial support。
文摘Hydrogen is a green clean fuel and chemical feedstock. Its separation and purification from hydrogencontaining mixtures is the key step in the production of hydrogen with high purity(>99.99%). In this work, carbon molecular sieve(CMS) membranes with ultrahigh permselectivity for hydrogen purification were fabricated by high-temperature(700–900 ℃) pyrolysis of polymeric precursor of phenolphthaleinbased cardo poly(arylene ether ketone)(PEK-C). The evolution of the microstructural texture and ultramicroporous structure and gas separation performance of the CMS membrane were characterized via TG-MS, FT-IR, XRD, TEM, CO2 sorption analysis and gas permeation measurements. CMS membranes prepared at 700 ℃ exhibited amorphous turbostratic carbon structures and high H2 permeability of 5260 Barrer with H2/CH4, H2/N2 and H2/CO selectivities of 311, 142, 75, respectively. When carbonized at900 ℃, the CMS membrane with ultrahigh H2/CH4 selectivity of 1859 was derived owing to the formation of the dense and ordered carbon structure. CMS membranes with ultrahigh permselectivity exhibit an attractive application prospect in hydrogen purification.
基金This research was supported by the National Key Research and Development Program of China(2017YFC1103900)the National Natural Science Foundation of China(81671837,81871502)+1 种基金the Shanghai Collaborative Innovation Program on Regenerative Medicine and Stem Cell Research(2019CXJQ01)Clinical Research Plan of SHDC(SHDC2020CR2045B).
文摘Tissue-engineered cartilage regeneration by bone marrow stromal cells(BMSCs)is considered an ideal method.However,how to regulate BMSCs to regenerate specific types of cartilage remains unclear,which significantly limits its clinical translation and leads to suboptimal clinical effects.Herein,we systematically explored the role of native ear and articular cartilage niches on the differentiation fate of BMSCs and the type of regenerated cartilage.First,we prepared two types of acellular cartilage sheets(ACSs)and two types of chondrocytes.Then green fluorescent protein-labeled BMSCs were seeded on two types of ACSs with or without corresponding types of chondrocytes using a sandwich model and directed or cross-implanted them into native cartilage niches.After one year of in vivo culture,cell tracking and the results of histological results showed that the native cartilage niches were capable of regulating BMSCs regeneration into specific types of cartilage that were consistent with the cartilage types of the implanted sites.Furthermore,even when the type of niche formed by ACSs or the biomimetic cartilage niche constructed by specific types of ACSs and specific types of chondrocytes did not match with the native cartilage niche,the native cartilage niche continued to determine the type of cartilage regenerated by implanted BMSCs and chondrocytes.All our results provide sufficient evidence for specific types of cartilage regeneration using chondrogenic potential cells,such as mesenchymal stem cells and chondrocytes.
